Fall in zone 5bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 51558 (Moorhead, IA)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Castana EXP Farm, IA (10 miles away).
- Average last spring frostApr 2550% chance of a 32°F freeze after this date
- Average first fall frostOct 1250% chance of a 32°F freeze by this date
- Growing season (frost-free)170 daysmedian, 32°F threshold
- USDA hardiness zone5b-15 to -10°F avg. coldest night
Get The Dial for 51558 (Moorhead)
Frost and freeze alerts from the NWS forecast for 51558, the spring soil-temperature heads-up for pre-emergent, and a short weekly yard-timing email.
- Freeze alerts
- Soil-temp heads-up
- Weekly yard to-dos
Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.
This week in your yard
As of Oct 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
53°F 50–55°F
24-hour average · latest 53°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Shagbark Hills (37 mi).
4-inch depth
53°F 50–55°F
24-hour average · latest 53°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Shagbark Hills (37 mi).
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 51558 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 53°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent window is mostly past. Next: spring, when soil reaches 50°F (typically mid-April to early May).
Fertilizer window
Lawn region: North (cool-season). Timing only; always follow the product label.
- Kentucky bluegrass (cool-season): Early fall: Around Labor Day (late August–September); Late fall: Late October–November, before the ground freezes; Late spring: Optional around Memorial Day. Avoid: Early-spring and midsummer feeding (pushes top growth, favors crabgrass).
Plant now
No vegetable planting windows are open this week.
Prune now
No frost-timed pruning windows are open this week.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | Apr 11 |
| 50% (the "average" last frost) | Apr 25 |
| 10% (cautious: only 1 year in 10 freezes later) | May 7 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Sep 28 |
| 50% (the "average" first frost) | Oct 12 |
| 90% (late: most years have frozen by now) | Oct 27 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 4 | Oct 3 |
| 32°F (freeze) | Apr 25 | Oct 12 |
| 28°F (hard freeze) | Apr 15 | Oct 23 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 51558
Dates count from your average last spring frost (Apr 25) and first fall frost (Oct 12). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Feb 28–Mar 14 | May 2–16 (transplant) | – |
| Pepper (sweet and hot) | Feb 14–28 | May 9–23 (transplant) | – |
| Eggplant | Feb 14–28 | May 9–23 (transplant) | – |
| Tomatillo | Feb 28–Mar 14 | May 2–16 (transplant) | – |
| Lettuce | Feb 28–Mar 14 | Apr 4–25 (transplant) Mar 28–May 9 (sow outdoors) | Aug 17–Sep 7 (transplant) Aug 3–31 (sowing) |
| Spinach | – | Mar 14–Apr 4 (sow outdoors) | Aug 17–Sep 7 (sowing) |
| Kale | Feb 28–Mar 14 | Mar 28–Apr 11 (transplant) Mar 28–Apr 11 (sow outdoors) | Jul 20–Aug 17 (transplant) Jul 6–Aug 3 (sowing) |
| Collards | Feb 28–Mar 14 | Mar 28–Apr 25 (transplant) Mar 28–Apr 25 (sow outdoors) | Jul 20–Aug 17 (transplant) Jul 6–Aug 3 (sowing) |
| Broccoli | Feb 14–28 | Mar 28–Apr 11 (transplant) | Jul 6–Aug 3 (transplant) |
| Cabbage | Feb 14–28 | Mar 28–Apr 11 (transplant) | Jul 6–Aug 3 (transplant) |
| Cauliflower | Feb 14–28 | Apr 11–25 (transplant) | Jul 6–Aug 3 (transplant) |
| Brussels sprouts | Jan 31–Feb 14 | Mar 28–Apr 11 (transplant) | Jun 22–Jul 13 (transplant) |
| Kohlrabi | Feb 28–Mar 14 | Mar 28–Apr 11 (transplant) Mar 28–Apr 11 (sow outdoors) | Aug 3–17 (sowing) |
| Bok choy / Asian greens | – | Mar 28–Apr 11 (sow outdoors) | Aug 17–31 (sowing) |
| Arugula | – | Mar 28–Apr 25 (sow outdoors) | Aug 17–Sep 14 (sowing) |
| Mustard greens | – | Mar 28–Apr 18 (sow outdoors) | Aug 17–31 (sowing) |
| Swiss chard | Mar 14–28 | Apr 11–May 2 (transplant) Apr 11–May 9 (sow outdoors) | Aug 3–17 (sowing) |
| Beet | – | Mar 28–Apr 25 (sow outdoors) | Aug 3–17 (sowing) |
| Carrot | – | Apr 4–May 2 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Radish | – | Mar 21–May 2 (sow outdoors) | Aug 31–Sep 14 (sowing) |
| Turnip | – | Mar 28–Apr 18 (sow outdoors) | Aug 3–17 (sowing) |
| Parsnip | – | Apr 4–25 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Feb 28–Mar 28 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Onion (bulbing) | Jan 31–Feb 14 | Mar 14–28 (transplant) | – |
| Green onion / scallion | – | Mar 14–Apr 11 (sow outdoors) | Aug 3–17 (sowing) |
| Leek | Jan 31–Feb 14 | Mar 28–Apr 11 (transplant) | – |
| Garlic | – | – | Aug 31–Sep 28 (sowing) |
| Shallot | – | Mar 14–28 (transplant) | Aug 31–Sep 28 (sowing) |
| Potato | – | Mar 28–Apr 11 (transplant) | Jun 22–Jul 6 (transplant) |
| Sweet potato | – | May 16–30 (transplant) | – |
| Sweet corn | – | May 2–16 (sow outdoors) | – |
| Bean, bush (snap) | – | May 2–16 (sow outdoors) | – |
| Bean, pole | – | May 2–16 (sow outdoors) | – |
| Lima bean | – | May 9–23 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 16–Jun 6 (sow outdoors) | – |
| Cucumber | Mar 28–Apr 4 | May 2–16 (transplant) May 2–16 (sow outdoors) | – |
| Summer squash / zucchini | Mar 28–Apr 4 | May 2–16 (transplant) May 2–16 (sow outdoors) | – |
| Winter squash | Mar 28–Apr 4 | May 2–16 (transplant) May 2–16 (sow outdoors) | – |
| Pumpkin | – | May 2–16 (sow outdoors) | – |
| Watermelon | Mar 28–Apr 4 | May 9–23 (transplant) May 9–23 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 28–Apr 4 | May 9–23 (transplant) May 9–23 (sow outdoors) | – |
| Okra | Mar 14–28 | May 9–23 (transplant) May 9–23 (sow outdoors) | – |
| Celery | Jan 31–Feb 14 | May 2–9 (transplant) | – |
| Basil | Mar 14–28 | May 2–16 (transplant) May 2–16 (sow outdoors) | – |
| Cilantro | – | Apr 11–May 9 (sow outdoors) | Aug 17–31 (sowing) |
| Parsley | Feb 14–28 | Apr 11–25 (transplant) Apr 4–25 (sow outdoors) | – |
| Dill | – | Apr 25–May 9 (sow outdoors) | Aug 17–31 (sowing) |
| Sunflower | – | Apr 25–May 9 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 28–Apr 11 (transplant) | – |
| Rhubarb (crowns) | – | Mar 28–Apr 11 (transplant) | – |
| Strawberry (plants) | – | Mar 28–Apr 11 (transplant) | Aug 3–31 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Where these numbers come from
Station: Castana EXP Farm, IA (NOAA GHCN-Daily ID USC00131277), elevation 1,400 ft, 10.4 miles from the ZIP's center point. NOAA completeness flag: S (standard, 24+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Little Sioux 2 NW, IA | 11 mi | May 1 | Oct 3 |
| Onawa 3NW, IA | 16 mi | May 1 | Oct 3 |
| Mapleton NO.2, IA | 18 mi | May 3 | Oct 1 |
The average last-frost dates of these stations span 9 days, a rough guide to local variation. See data sources & methods.
Frost questions for 51558
When is the last frost in 51558?
The average (50% chance) last spring freeze of 32°F for ZIP 51558 is April 25. For a more cautious planting date, use May 7, when only 1 year in 10 still sees a later freeze.
When is the first frost in 51558?
The average first fall freeze is October 12. In 1 year in 10 it comes by September 28.
What hardiness zone is 51558?
ZIP 51558 is in USDA zone 5b (-15 to -10°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 51558 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
51572 Soldier 51564 Pisgah 51545 River Sioux 51523 Blencoe 51040 Onawa 51529 Dunlap 51010 Castana 51060 Ute
Other ZIP codes in Monona County
51010 51034 51040 51051 51060 51063 51523 51572 All Monona County frost dates · Iowa frost dates
Never miss a frost: get The Dial
Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
- Soil-temp heads-up
- Weekly yard to-dos
Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.